Dry electrolytic condenser



Feb. 16, 1937. M, BER TEW 2,071,104

DRY ELECTROLYT I C CONDENSER Filed May 18, 1931 INVENTOR Milton Bergstein BY ATTORN EY Patented Feb. 16, 1937 I I UNITED STATES PATENT OFFICE 2.071.104 DRY ELECTROLYTIC coNnENsER Milton Bergstein, New York, N. Y., assignor to Micamold Radio Corporation, Brooklyn, N. Y., a corporation of New York Application May 18, 1931, Serial No. 538,401

7 Claims. (Cl. 175- 315) In my copending application, Serial Number as to render the use of the latter impractical. 538,399, filed May 18, 1931, entitled Electrolytic Ordinary commercial grades of triethanol amcondenser I have described and claimed elecmonium soaps are satisfactory for the above purtrolytic condensers wherein soaps or mixtures of pose, high purity being unnecessary, and elec- 5 soaps and fatty acids were employed as constitutrolytes of the above nature have the advan- 5 ents of the electrolyte in condensers of the dry tage of lower cost and more easy application electrolytic type, ammonium soaps being preas compared to gum arabic, glycol, glycerol, ferred on account of thelower solvent action of glucose borate mixtures and the like which are the ammonium ion on the aluminum oxide film commonly employed.

10 of the condenser. I may modify the electrolytes of the types above 10 I have further discovered that the acitivity of described by the addition of 'a small quantity, the ammonium ion in electrolytes of the above for example, 5% by weight of a weak organic character can be modified by the substitution acid such as stearic acid, thereby decreasing the for the hydrogen atoms of suitable alkyls or aging period of the condenser and obtaining alkyl derivatives. For example, the methyl and somewhat higher conductivity in the electrolyte 15 ethyl ammonium ions are more alkaline, and and consequent higher effective capacity; or an methanol or ethanol derivatives less alkaline equivalent quantity of acid salt of acids of the than the unsubstituted ions. above type may be added for similar purposes,

As typical of the compounds capable of giving such as ammonium or aluminum acetate. I find the effects desired, reference is made to the trithat a convenient way for preparing the alu- 20 ethanol ammonium compounds which have the minum acetate is by the addition of one part advantage of ready commercial availability, of glacial acetic acid to about one and one-half, although other alcohol substituted ammonium parts by weight of aluminum oxide, yielding a compounds may be employed. mixture of aluminum acetate, aluminum hy- Triethanol ammonium scans such as stearate, droxide andaluminum oxide. The excess of 5 palmitate or mixtures thereo are quite satisaluminum oxide furnishes aluminum ion within factory for electrolytic pu ises, their consistthe electrolyte, thus cutting down the solvent ency being suitable when in solid form and beeffect of the electrolyte upon the aluminum ox-. cause they can be heated to the melting point ide coat of the electrolyte.

without loss of triethanolamine and consequent A preferred form of condenser employing the 30 rapid change in composition, a somewhat obelectrolyte above described is shown in the acjectionable feature in'ammonium soaps. Furcompanying drawing wherein Fig. 1 is a perthermore, their ready fluidity when in liquid spective view of the condenser partially unrolled, form makes it easy to apply them to gauze or and Fig. 2 is an enlarged cross-sectional view 5 other suitable separating medium employed betaken through the condenser along the line 2-2 tween the armatures of the condenser. of Fig. 1.

I have found that an electrolyte consisting of In the drawing, the numeral l es gnates one triethanol ammonium stearate can be employed electrode with its terminal 2. The other elecwithout the addition of any other substances trade is designat d y 3 With its e inal shown 40 whatsoever as the electrolytic conductor in conat 4. Between the electrodes are layers of 40 densers of the above type, it being merely necesauze 5 and 6 impr w h h lectrolyte.

saryto melt the electrolyte and apply it to a I claim: suitable separator medium as known in the art. 1. An electrolytic condenser of the class de- I have further found that the addition of triscribed having an armature of the film-forming ethanol ammonium linoleate lends further detype. and an electrolyte consisting of a tri- 45 sirable properties; for example, the resistance ethanol ammonium soap.

1 of the electrolyte may be thereby reduced and 2. An electrolytic condenser of the class dethe effective capacity increased. A mixture in scribed having an armature of the film-forming the ratio of two parts by weight of stearate type, and an electrolyte consisting of a mixture ,to one part of linoleate, for example, is satisof triethanol ammonium soaps. 5o factory. The unmixed stearate, however, has 3. An electrolytic condenser of the class dethe advantage of greater solidity, and the necesscribed having an armature of the film-forming sary period of aging of the condenser is also type, and an electrolyte consisting of a mixture somewhat increased by the addition of ammoof triethanol ammonium stearate and triethanol 5s nium linoleate, although not to such an extent mmonium lin ea 66 ing an alcohol substituted ammonium ion and the ion of a weak organic acid.

6. An electrolyte consisting of a soap produced by the reaction of a soap-forming acid and an alcohol substituted amine.

'7. An electrolyte consisting of an ethanol ammonium soap.

MILTON BERGSTEIN. 

